The purpose of this proposal is to isolate and characterize clinically significant allergens from both American and German cockroach species and define their role as sensitizing/exacerbating agents in asthma. Employing standard immunochemical techniques (e.g., column chromatography, preparative isoelectric focusing and immunoprinting), allergens will be extracted and fractionated from cockroach whole bodies and feces. Purified fractions (in addition to crude extract) will be utilized in both intracutaneous and direct RAST/RAST inhibition studies to define specific cockroach allergens. Rabbit antisera produced against whole body and fecal extracts will be used in the methods of crossed immunoelectrophoresis, crossed line immunoelectrophoresis and crossed radioimmunoelectrophoresis to investigate the occurrence of common/shared antigens/allergens among German and American cockroach whole bodies and feces. RAST inhibition, crossed line radioimmunoelectrophoresis and immunoprinting will be used to identify cockroach allergens in samples of house dust. Dust specimens will be collected by Accu Vol aeroallergen samplers and are therefore representative of "airborne" sources of cockroach allergens. American and German cockroach crude whole body extracts will be employed in bronchoprovocation studies to establish the link between cockroach sensitization and the induction of allergic respiratory disease (asthma). Collectively, these studies will both enhance our understanding of inhalant cockroach allergens, which elicit significant morbidity in atopic individuals, and provide a rational approach for the selection of specific allergens for purposes of immunotherapy.